Exhaust gas hub



Jan. 10, 1933. T DICK; 1,893,820

EXHAUST GAS HUB Filed April 1. 1930 4 Sheets-Sheet;- l

INVENTOR T. A. DICKS EXHAUST GAS HUB Jan. 10, 1933.

///llllllllllll M4 W/W" T. A. DICKS EXHAUST GAS HUB Jan. 10, 1933.

4 sheetS sheet Filed April 1. 1930 R o T N E v m EXHAUST GAS HUB 4 Sheetsfiheet Filed April 1.

Jan. 10, 1933 UNETED STATES PATENT OFFICE THOMAS A. DICKS, OF PITTSBURGH, PENNSYLVANIA, ASSIGNOR TO PITTSBURGH SCREW AND BOLT CQRIPORATION, 0F PITTSBURGH, PENNSYLVANIA, A CORPORATION OF FENNSYLVAINIA EXHAUST GAS HUB Application filed April 1, 1930. Serial No. 4-40,?22.

This invention relates to hollow hubs for engines of the aeronautical type and is in particular a hollow hub having radial blade receiving sockets for the reception of hollow propeller blades, the hub being securable to and rotatable with the engine shaft in the usual manner.

One of the objects of the present invention is to provide a sturdy, substantially unitary hub which is designed to receive exhaust gases from an associated motor and to direct said gases into the hollow propeller blades whence they are discharged.

Another object of the invention is the provision of a hollow hub from which the exhaust gases are kept out of intimate contact in order to avoid over-heating and in which additional air passages are provided for the positive cooling of the same.

Another object of the invention is the provision of a removable bell-shaped member which. when in position. assists in directing the exhaust gases into the blade sockets and hence into the blades themselves, said bellshaped member preventing the exhaust gases from contacting with the body portion of the hub and also communicating with the cooling air passages.

A further object of the invention is the provision ot a gas collecting ring associable withthe hub and bell-shaped member for directing the exhaust gas from the cylinders of the motor to the blade sockets.

Other and further objects of the invention will be understood by those skilled in this particular art.

In the accompanying drawings:

Figure 1 is a plan of the hub with the bellshaped member shown in dotted line position.

Fig. 2 is a plan of the hub partly in crosssection. with the bell-shaped member in postion therein.

Fig. 3 is a view partly in elevation and partly in cross-section of the hub and associated blade sockets.

Fig. l is a plan View partly in crosssection at right angles to Fig. 1 showing the gas collector ring and removable bell-shaped member.

Fig. 5 is an elevational view of the gas colleetor ring per se.

Fig. 6 is a view looking down on Fig. 5.

Fig. 7 is a view looking at Fig. 5 from the indicated angle.

Fig. 8 is a plan view of one of the hollow blades utilized with the present hub.

Fig. 9 is a View of the rear of the blade of Fig. 8 at ri ht angles thereto showing the discharging s ots and showing the root of the blade in cross-section.

Fig. 10 is a section on the line XX of Fig. 9 and then turned through an angle of ninety degrees.

Fig. 11 is a section taken on line XIXT of Fig. 9 showing the application of an end mill for cutting slots.

Fig. 12 is a section taken on the line XII-XII of Fig. 9.

Referring now to the drawings in detail;

The propeller hub body portion is indicated at 10 and passing through said body portion are the passages 11 indicated best in Figs. 3

and 4, associated with preferably unitarily associated propeller blade sockets 12 which are radially disposed and of any preferred number, as usual in this art. Hollow propeller blades 13 are adapted to be inserted in these sockets and may be secured therein in any desired manner such as indicated at 14.

Each blade has a cut-out portion 15. the purpose of which will be hereinafter apparent and also a pair of diametrically opposite apertures 16 for the reception therethrough of the usual tightening bolt assembly such as indicated at 17.

It will be noted particularly from Fig. 2 that there is an annular groove 18 formed in the hub and by referring to Fig. 4 it will be seen that the gas collector ring 19 cooperates therewith so that the shoulders 20 and 21 on the hub and ring, respectively, form an interlocking fit which, moreover, prevents any gases from escaping therearound.

The collector ring is of the form clearly shown by referring to Figs. 5, 6 and 7 and in general it comprises a tubular portion 22 having appropriate apertures 23 therein for cooperating with the various cylinders of the motor (not shown) which, in the present instance, would be a nine cylinder radial engine. Formed to project from the tubular portion are lugs 24 which, as clearly shown in Fig. 4, are adapted to be appropriately secured at 25 to the proper part of the motor or the like, which is fragmentarily illustrated at 26.

By referring especially to Figs. 2 and 4 it will be seen that there is a bell-shaped member 27 which is shaped at 28 to provide an interlocking shoulder arrangement with the adjacent portion 29 of the hub. The outer end of the bell-shaped member 27 is rovided wth exterior screw-threads 30 and these are adapted to cooperate with internal screw threads appropriately formed at 31 in the hub. It will thus be seen that by unscrewing the bellshaped member outwardly, that member can be conveniently removed and this permits unusual access to the various portions of the hub for reasons which require no part cular discussion.

It is understood that each of the: various openings 23 in the gas collecting ring is suitably connected to the exhaust pipe (not shown) from each engine cylinder and hence that the exhaust gases which are discharged therefrom, and wh'ch are still under appreciable pressure, enter the ring through the apertures. The gas then clearly passes into the radial blade sockets via an aperture 33 therein and is guided thereinto by the outer concave surface 32 of the bell-shaped member 27.

Into each socket is fitted and secured a hollow propeller blade 13 as aforesaid and arranged so that the cut-out portion 15 will cooperate with apertures 33 in the socket and receive the gases directed thereto by the ring 19 and bell-shaped member 27. Due not only to the fact that the gases are under pressure but also due to the fact that the gases are thrown outwardly by centrifugal force by the rapid rotation of the blades and hub, it will be understood that the gases pass into the blade and toward the tip thereof and that the slots 34 formed in one surface of the blade permit the discharge of the gases into the atmosphere and in order to enhance the discharging effect the slots are placed so that their out-lets are at or close to the trailing edge of the blade at wh ch point there is probably a partial vacuum which again assists in efficient and noiseless discharge of the exhaust gases. The root of the blade may be formed in any desirable way such as by thickening the portions 35 through which the apertures are formed for receiving the bolt assemblies, but such constitutes no part of the present invention.

It will further be seen. particularly from Figs. 2 and 4 that as the hub travels through the air. in the direction of the plane, of course, the air enters the circular row of air passages 11, thereby keeping the hub cool.

wall of the bell-shaped member.

At one end, the air passages communicate with the interior of the bell-shaped member 27 there being a heat exchange through the The exhaust gases are kept sufliciently cool and at the same time the volume of air passing through the passages and the bell-shaped member are sufficient to keep the hub itself sufficiently cool as it is not good practice that the same should be allowed to become relatively over heated.

Various minor details of the constructIon illustrated in the drawings will be understood as it forms no part of the present invention and is merely presented to form a sufficiently complete picture to make the application of the present invention clear.

In cutt ng the slots 34 in the blades 13, an end mill 36 of suitable type may be used and such a mill may be manipulated convenient- 1y to obtain slots having no sharp corners. The two slots nearest the tip of the blade are substantially semi-circular and are formed by cutting out one blade surface correspondingly. It is understood that the slots are out only in one surface of the blade and that the opposite surface is uncut.

Suitable provisions of course are made for the reception of the engine shaft in the hub and the securing of shaft and hub in position but such need no particular discussion as they form no part of the present invention.

I am not limited, of course, to a gas collecting ring having n ne apertures for receiving gas from the cylinders of a nine-cylinder motor, but it is evident that I may vary the spacing and number of openings so as to adapt it for a motor having any number of cylinders.

The surface 18' (Figs. 1 and 2) is provided and, as shown in Fig. 4, forms a hearing surface which rotates against the inner side of the gas collecting ring 19. In other words. the gas collecting ring is stationary whereas the hub and bell-shaped member rotate with the shaft. The relative rotation occurs between the ring 19 and surface 18' as will be clearly understood from Fig. 4. These members make a close but not a t ght fit and the slight clearance between them, shown in somewhat exaggerated manner in Fig. 4, is filled with oil, thus the rotating parts rotate on an oil film.

The shoulder 21 thus fits into groove 18 with a small clearance therehetween and there is also a slight clearance between surface 18 and the inner contact ng surface of the ring 19.

hat I claim as new and desire to secure by Letters Patent is:

1. In an exhaust gas hub for aeronautical type engines, a body portion having blade receiving sockets and a gas collecting ring member, means for interlocking said gas eollccting ring member and sockets, a member for directing said gas into said sockets and for kee ing said gas from contacting with said bod portion, and air passages or keeping said hub relatively cool. 2. In an exhaust gas hub for aeronautical type engines, a body portion having blade receiving sockets and a gas collecting ring member, a bell-shaped member cooperating with said body portion and collecting ring, gas from an associated engine being directed into said sockets via said collecting ring and kept out of contact with said bo y portion by said bell-shaped member, and air passages communicating with the other side of the bell-shaped member for cooling said hub. 3. In an exhaust gas hub for aeronautical t pe engines, a body portion having radially disposed blade receiving sockets and an engine gas collecting ring, said gas collecting ring communicating with said sockets, a removable bell-shaped member cooperating with said body portion and collecting ring, whereby said engine gas is directed into said sockets and kept from contacting with said body portion proper, and air passages thigough said body portion for cooling said hu 4. In an exhaust gas hub for aeronautical type engines, a body portion having radially disposed blade receiving sockets and an engine gas collecting ring, said gas collecting ring communicating with said sockets, a removable bell-shaped member cooperating with said body portion andcollecting ring, whereby said engine gas is directed into said sockets and kept from contacting with said body proper, air passa es throu h said body portion for cooling sai hub, an hollow propeller blades in said sockets having exits for said a.

5. Iii an exhaust gas hub for aeronautical t pe engines, a body portion having radially disposed blade receiving sockets, and an engine gas collecting ring, said gas collecting ring communicating with said sockets, a removable bell-shaped member cooperating with said body portion and collecting ring, whereby said engine gas is directed into said sockets and kept from contacting with said body portion proper a circular row of air passages through said body portion for cooling said hub, and hollow propeller blades in said sockets havin generally tangential exits in the trailing e ges thereof.

6. In a device of the class described, abellshaped member having a shoulder at one end and being screw-threaded at the other end.

7. In a device of the class described, a bell-shaped detachable member having an annular shoulder at one end, and being exteriorly threaded at its other end, said member being concave intermediate said ends.

8. In an exhaust gas hub for aeronautical type engines, a solid hub body having a concentric row of air passages therethrough, ra-

dial blade sockets on said hub body, an annular shoulder on said hub defining an annular groove, a gas collecting ring mounted so as to be stationar with respect to said hub and provided with an annular shoulder projecting into the annular oove in the hub aforesaid, said ring receiving exhaust gas from an associated engine, said hub also having a shoulder and screw threads for the reception of a member complementarily formed for directing exhaust gas into said sockets, which are apertured for communication with said ring, and for directing air into said air passages, as well as for maintainin said exhaust ases out of contact with sai hub, and a mem er as aforesaid.

9. In an exhaust gas hub for aeronautical type engines, a solid hub body having a concentric row of air passages therethrough, radial blade sockets on said hub body, an annular shoulder on said hub defining an annular groove, a gas collecting ring mounted so as to be stationary with respect to said hub and rovided with an annular shoulder ro'ecting into the annular groove in the hub a oresald, said ring receivin exhaust gas from an associated engine, said hub also having a shoulder and screw threads for the reception of a member complementarily formed for directing exhaust gas into said sockets, which are apertured for communication with said ring, and for directing air into said air passages, as well as for maintaining said exhaust gases out of contact with said hub, and a member as aforesaid, said member being concavo-convex intermediate its rearward end and its forward flared externally threaded mouth.

. In testimony whereof, I have hereunto subscribed my name this 29th day of March,

THOMAS A. DICKS. 

